Writing board



J. c. NELSON 3,084,956

WRITING BOARD Filed Sept. 29, 1958 April 9, 1963 (BI/M455 EJ245014 INVENTOR.

snsasss WRETKNG BQA RD .iarnes C. Nelson, 324 Pasrgual St., San Gabriel, Calif. Filed Sept. 2), 1%"8, Ser. No. 764,6?3 in Claims. ct. asa zs This invention relates to improved writing board devices for use in the keeping of accounting records.

In certain types of accounting systems, it is customary to utilize writing boards on which two or more record sheets of difierent types can be placed, one above the other, and with carbon paper being received between the successive sheets, so that a record of a particular transaction can be made on all of the sheets simultaneously. For example, one of the sheets might be a ledger page, a second sheet might be a journal page, and the third sheet might be another record on which the same transaction is to be recorded.

The general object of the present invention is to provide a writing board which is especially adapted for this type of multiple sheet use, and which is extremely versatile for assuring maximum facility in positioning the sheets on the writing board, and yet which at the same time is structurally extremely simple. In a device embodying the invention, an upper one or more of the sheets are so attached to the device as to be readily shiftable relative to the bottom record sheet, in a manner permitting the positioning of any desired line on the upper sheet or sheets in alignment with a proper line on the lower sheet. This result is achieved by providing along one side of the writing board a shiftable rail, to which an upper sheet or sheets are connectable in a manner such that when the shiftable rail is moved longitudinally, this movement acts to correspondingly shift the associated sheet or sheets relative to the writing board and relative to another record sheet which is positioned on the writing board.

Of particular importance to the present invention is a unique manner in which the bottom one of the record sheets is secured to the writing board by the shiftable rail itself, without the necessity for the provision of any additional retaining parts for attaching the sheet to the board. For this purpose, the rail is so constructed and positioned that the edge of the lowermost record sheet can be received beneath the rail, and vertically between the rail and the edge of the writing board, so that the sheet is held in position by confinement between these two parts. Suitable means are provided on the board for guiding the rail for its desired longitudinal shifting movement, with these means being so constructed as to allow sufficient looseness to permit the shifting of the rail while the edge of the bottom sheet is positioned therebeneath. Also, there are desirably provided on the writing board means for positively retaining the bottom sheet against movement with the rail when the latter is shifted to different positions. These means may consist of one or more projections extending upwardly from the board at the underside of the record sheet, preferably a series of such projections spaced apart longitudinally of the rail.

For maximum simplicity, the writing board may be formed of a single sheet of metal, one of whose edges may be doubled hack to form a guideway or channel which guides the shiftable rail for its longitudinal movement. Also, the projections which retain the bottom record sheet against movement with the rail relative to the board may be formed very simply as small lugs stamped out of the metal of the writing board itself. These lugs may be so located as to serve a secondary function of retaining the rail against lateral movement out of its guide way, and thus assisting in guiding the rail for only the desired longitudinal shifting movement.

3,@34,95i5 Patented Apr. 9, 1953 The above and other features and objects of the present invention will be better understood from the following detailed description of the typical embodiment illustrated in the accompanying drawing in which:

FIG. 1 is a perspective view showing a device constructed in accordance with the invention;

FIG. 2 is an enlarged fragmentary plan view, partially broken away, showing a corner portion of the upper side of the FIG. 1 device;

FIG. 3 is a further enlarged fragmentary section taken on line 33 of FIG. 2;

FIG. 4 is a greatly enlarged fragmentary perspective view of one of the projections which holds the bottom record sheet against movement relative to the writing board;

FIG. 5 is a view showing the manner in which the present device can be positioned in a looseleaf record book; and

FIG. 6 is an enlarged perspective view of one of the pegs on the shiftable rail.

Referring first to FIG. 1, the device embodying the invention is represented generally at 1'9, and is shown in that figure as it appears when three different record sheets 11, 12 and :13 are positioned on the board in superimposed relation. The bottom one of these record sheets, No. 11, which is normally considerably larger than the other two sheets, may typically be a journal page, while sheet 12 may be a ledger page, and upper sheet 13 may be a statement'. Carbon papers are positioned between these successive sheets, so that anything written on the top sheet will be recorded also on the two other sheets 11 and 12.

The device 10 includes a writing board 14, which may be a rigid sheet of steel or other metal. This board 14 is planar except at its left edge where it is deformed in a manner later to be described to retain and guide the shiftable rail 15 to which sheets :12 and 13 are attached. As will be apparent, the three record sheets 11, 12 and 13 are placed on the upper writing surface of board 14, so that the board forms a backing for the sheets while entries are being made thereon.

The rail 15 which is mounted to the left edge portion of writing board 14 serves to carry and position the two upper record sheets 12 and 13. This rail 15 may be formed of a single elongated essentially rectangular strip of rigid sheet metal, the material of which is pierced and deformed at a series of spaced locations in a manner forming a series of longitudinally spaced lugs or pegs 16 which project upwardly or outwardly from rail 15 in a direction essentially perpendicular to the upper Writing surface of board 14. Except at the locations of pegs. 16, the sheet metal rail 15 is preferably planar, lying in a plane which is parallel to but spaced slightly above or outwardly from the upper writing surface of main board 14. The rail 15 is elongated in a direction parallel to the left edge 17 of board is, and extends along substantially the entire extent of that edge 17. Pegs 16 are spaced apart uniformly in the direction of edge 17 of the board, that is, longitudinally of rail 15. These pegs or projections 16 may be of the elongated cross-sectional configuration represented in FIG. 2, to be receivable within any of the various correspondingly shaped elongated slots 18 formed along the left edge portions of the two upper sheets 12 and 13. Aper-tures 18 may be provided at more closely spaced locations than are pegs 16, to allow for any desired relative positioning of sheet 13 relative to sheet 12. As will be understood, the positioning of the pegs 16 and apertures 18 is such that, when the two sheets 12 and 13 are attached to rail 15 by reception of pegs 16 within any of the different apertures 18, the writing lines on the two sheets 12 and 13 will extend directly parallel to the upper and lower edges 19 3 and 20 of board 14, and therefore parallel to the writing lines on the bottom sheet 11 attached to that board.

To describe the pegs 16 somewhat more specifically, it is noted that each peg may be formed by piercing or cutting the material of rail 15 at the peg location in a manner forming two apertures 16a and 16b (see FIG. 6), and deforming the material of the rail upwardly from within and between those apertures to produce one of the pegs. When formed in this way, each of the pegs consists of two halves which meet along a line 16c at the center of the peg.

The rail 15 is mounted to board 14 for longitudinal shifting movement of the rail, in the direction of left edge 17 of the board. To guide the rail for this movement, the left edge portion 17 of the board is turned upwardly at '21, and is then doubled back at 22 to extend parallel to the main portion of the board but at a location spaced above its upper surface. This doubled back edge portion 22 of the board thus forms a narrow guide way within which the left edge of the planar portion of rail 15 is slidably received and confined (see FIG. 3). Pegs v16 are of course located sufficiently far to the right on rail 15 to be positioned laterally beyond the extreme edge 23 of the doubled back portion 22 of the board. As is best brought out in FIG. 2, the rail' 15 is defined along its opposite sides by a pair of parallel edges 24 and 25, the left one of which is engageable with the up-turned portion 21 of board 14 to laterally confine rail 15 against leftward movement relative to the board.

The left edge portion 26 of bottom record sheet 11 extends laterally to a location beneath shiftable rail '15, and into the guide way formed beneath doubled back portion 22 of the board, into substantial engagement with the upwardly extending portion 21 of the board. As will be apparent from FIG. .3, the guide way formed beneath portion 22 of the board is sufficiently thicker or deeper than the contained sheet metal of rail 15 to allow [for the reception of the edge portion 26 of sheet :11 vertically between the rail and the edge of the board, while at the same time allowing longitudinal adjusting movement of the rail relative to the board and relative to sheet 11. Such adjusting movement of the rail of course shifts sheets 12 and 13 relative to bottom sheet 11, to so position all of the sheets as to locate a particular entry on the proper lines of the different sheets.

In order to positively hold bottom sheet 11 against movement relative to board 14 when rail 15 and the carried sheets 12 and 13 are adjusted relative to the board, the sheet metal of board 14 is deformed in a manner forming a series of lugs or projections 27 extending upwardly from the upper surface of writing board 1 4, and of a height just sufiicient to slightly locally deform the paper of record sheet 11 in a manner effectively retaining the sheet against movement with rail 15, but without actually piercing or damaging sheet 11 in any way. These projections 27 are located just to the right of the right edge 25 of rail 15, and are spaced apart longitudinally of edge 25 of the rail in a manner serving a secondary function of confining the rail against rightward lateral movement, and thus coacting with the turned edge portion 22 of board 14 in guiding rail 15 for only longitudinal sliding movement (parallel to the left edge of board 14). As is brought out best in FIG. 3, the projections 27 do not actually engage rail 15 in order to perform this guiding function, but do deform sheet 11 upwardly sufiiciently at the locations of projections 27 to cause the sheets 11 to form small shoulders 28 for retaining rail against rig-htward movement. Each of the projections 27 may be produced by forming a cut 29 in the sheet metal of board 14, at a location spaced very slightly to the right of, but parallel to, right edge 25 of rail 15, following which the portion of the sheet metal of board 14- which is located just to the right of the cut 29 is deformed upwardly be yond the plane of the board, so that the edge 30 of that upwardly deformed portion is parallel to and in closely 4 spaced relation to edge 25 of the rail, and will cause the desired deformation of sheet 11 at 28 to confine the rail against rightward movement.

The bottom record sheet 11 is normally of a thickness between about .005 inch and .0055 inch, in which case the guideway formed by turned portion 22 of the board is of sufiicient thickness to receive the rail and also paper of this particular thickness within the guide way, While allowing relatively free sliding movement of the rail relative to the board and the paper. The projections 27 may'typically extend upwardly beyond the upper writing surface of board 14 a distance between about .025 and .027. As can be seen in FIG. 2, the left edge portion 26 of sheet 11 normally has a series of apertures 31 formed along that edge of the sheet, but these apertures are not utilized for positioning purposes in the present device.

Adjacent the right edge 32 of sheet 11, there may be provided a series of three apertures 33 for receiving the three rings 34 (see FIG. 5) of a loose leaf accounting book, when sheet 11 is positioned in such a book with a series of other similar sheets. Also, there are normally provided along edge 32 a pair of larger spaced apertures 35 for mounting the sheet 11 within a different type of loose leaf book if desired. In using the device 10 of the present invention, it is often desirable to position the entire device within an accounting book such as that shown at 36 in FIG. 5, with the proper page 11 of that book (and also associated sheets 12 and 13) positioned on the board 1 1- so that entries may be made on the sheets without removing sheet 11 or device 10 from the book. To thus position the device and the carried sheets within book'36, there are provided along right edge 38 of board 14 a series of three spaced apertures 37, coinciding with apertures 33 of sheet 11, so that both the board 14 and sheet 11 may be positively retained by rings 34 within book 36.

.To now describe the manner in which the device 10 is assembled for use, assume that initially none of the sheets 11, 12 or 13 are attached to the device. The first step is to slide rail 15 upwardly or downwardly until it is completely detached from board 14. following which the left edge portion of bot-tom record sheet 11 is positioned within the guide way formed by turned edge 22 of board 14. The rail 15 is then slid downwardly into that guide Way, but above the upper edge portion of sheet 11, to clamp that edge of sheet 11 relatively tightly in place vertically between rail 15 and the upper surface of board 14. The projections 27 effectively retain sheet 11 against movement with rail 15, as has been discussed previously, and also assist in guiding the rail for only the desired longitudinal movement. After the rail is in position within its guide way, the two sheets 12 and 13 are positioned on the guide rail in proper relative locations, being located relative to the rail by reception of pegs 16 within different ones of the apertures 18 formed in the two sheets 12 and 13. With the sheets 12 and 13 thus carried by rail 15, the rail is adjusted longitudinally to a position in which proper lines of the sheets 12 and 13 are located directly above a particular selected line on the bottom sheet 11. After carbon paper has been inserted between the various sheets, a user may Write any desired entry on the upper sheet 13, and that will be transmitted by the carbon paper to the pro'per lines on the other two sheets 12 and 11. In this way, three records are made simultaneously, to thus greatly simplify the accounting procedure. The shiftability of the two upper sheets relative to the lower one gives extreme versatility to the device, and this versatility is supplemented by the capacity of the device to be actually positioned in a loose leaf accounting book in the manner represented in FIG. 5.

. I claim:

I l. A bookkeeping device comprising a writing board on which a first record sheet may be placed, a peg rail extending along the upper surface of said board near one side edge thereof, said rail being adapted to receive an edge of said record sheet beneath the rail and vertically between the rail and board to retain the sheet on the board, said one side of the board being turned upwardly and then being doubled back above said rail and above and generally parallel to said upper surface of the board to form a guide channel slid ably receiving said rail and guiding it for longitudinal sliding movement while said edge of the second sheet is confined vertically between said rail and board, said rail having a plurality of pegs projecting upwardly therefrom and adapted to be received in corresponding apertures in the edge of a second record sheet overlying said firstsheet to locate said second sheet relative to the rail and thereby move the second sheet with the rail upon said shifting movement thereof, said pegs being positioned laterally beyond and projecting upwardly higher than said doubled back edge of the board, said rail having an undersunface for engaging said first sheet and slidable along the upper surface thereof upon said longitudinal shifting movement of the rail, and means projecting upwardly from said board at a location to engage the underside of said first sheet and hold it against movement with said rail when the latter is shifted longitudinally.

2. A bookkeeping device comprising a writing board on which a first record sheet may be placed, a peg rail extending along the upper surface of said board near one side edge thereof, said rail being adapted to receive an edge of said record sheet beneath the rail and verticallyl between the rail and board to retain the sheet on the board, said one side of the board being turned upwardly and then being doubled back above said rail and above and generally parallel to said upper surface of the board to form a guide channel slidably receiving said rail and guiding it for longitudinal sliding movement, said rail hav ing a plurality of pegs projecting upwardly therefrom and adapted to be received in corresponding apertures in the edge of a second record sheet overlying said first sheet to locate said second sheet relative to the rail and thereby move the second sheet with the rail upon said shifting movement thereof, said pegs being positioned laterally beyond and projecting upwardly higher than said double back edge of the board, and projections extending upwardly from said board and engageable with said first sheet in a relation retaining the latter against movement with said rail when the latter is shifted, said projections being so located as to laterally retain the rail against movement laterally out of said guide channel to thereby assist in guiding the rail for said longitudinal movement.

3. A device as recited in claim 2, in which said board is a single sheet of metal having said doubled back edge portion formed integrally therewith and having said projections formed by upwardly bent portions of the metal board itself.

4. A bookkeeping device comprising a writing board on which a first record sheet may be placed, a rail extending along the upper surface of said board near one side edge thereof, said rail being adapted to receive an edge of said record sheet beneath the rail and vertically between the rail and board to retain the sheet on the board, said rail having locating means for engaging an edge of a second record sheet which overlies the first sheet and operable to hold said second sheet in a predetermined position relative to the rail, means carried by the board guiding the rail for longitudinal shifting movement relative to the board and relative to said second sheet While said edge thereof is confined vertically between said rail and board to thereby shift said second sheet relative to said first sheet, said rail having an under surface for engaging said first sheet and slidable along the upper surface thereof upon said longitudinal shifting movement of the rail, and means projecting upwardly from said board at a location to engage the underside of said first sheet and hold it against movement With said rail when the latter is shifted longitudinally.

5. A bookkeeping device comprising a writing board on which a first record sheet may be placed, a rail extending along the upper surface of said board near one side edge thereof, said rail being adapted to receive an edge of said record sheet beneath the rail and vertically between the rail and board to retain the sheet on the board, said rail having locating means for engaging an edge of a second record sheet which overlies the first sheet and operable to hold said second sheet in a predetermined position relative to the rail, means carried by the board guiding the rail for longitudinal shifting movement relative to the board and relative to said second sheet while said edge thereof is confined vertically between said rail and board to thereby shift said second sheet relative to said first sheet, said rail having an under surface for engaging said first sheet and slidable along the upper surface thereof upon said longitudinal shifting movement of the rail, and means carried by the board projecting upwardly at the underside of said first sheet and engageable with the first sheet in a relation retaining it against movement with the rail when the latter is shifted longitudinally, said last mentioned means being positioned to retain the rail against lateral movement during said longitudinal movement thereof and to thereby function as a portion of said guiding means.

6. A bookkeeping device comprising a writing board on Which a first record sheet may be placed, a rail extending along the upper surface of said board near one side edge thereof, said rail being adapted to receive an edge of said record sheet beneath the rail and vertically between the rail and board to retain the sheet on the board, said rail having locating means for engaging an edge of a second record sheet which overlies the first sheet and operable to hold said second sheet in a predetermined position relative to the rail, and means carried by the board guiding the rail for longitudinal shifting movement relative to the board and relative to said second sheet while said edge thereof is confined vertically between said rail and board to thereby shift said second sheet relative to said first sheet, said rail having an undersurface for engaging said first sheet and slidable along the upper surface thereof upon said longitudinal shifting movement of the rail, said guiding means comprising an edge of said board doubled back above and generally parallel to said upper surface thereof to form a guide channel for slidably receiving said rail.

7. In an accounting board device, the combination of: a support member having a substantially fiat working surface, a lip extending along one edge of the support member overlying a portion of said surface, a series of abutment elements formed integrally with the support member and projecting above the working surface, said series extending parallel to said lip, a peg rail having parallel edges and provided with a plurality of upstanding pegs spaced longitudinally thereof, said lip and abutments cooperating to guide the edges of the peg rail so that it may move longitudinally relative to the support member, said lip overlying one of the edges of the peg rail, whereby the peg rail may cooperate with the lip and abutments to clamp a base sheet in position on the working surface of the support member.

8. In an accounting board device, the combination of: a support member having a substantially fiat working surface, a lip extending along one edge of the support member overlying a portion of said surface, a series of abutment elements carried by the support member at fixed locations relative thereto and projecting above the working surface, said series extending parallel to said lip, a peg rail having parallel edges and provided with a plurality of upstanding pegs spaced longitudinally thereof, said lip and abutments cooperating to guide the edges of the peg rail so that it may move longitudinally relative to the support member, said lip overlying one of the edges of the peg rail, whereby the peg rail may cooperate with the lip and abutments to clamp a base sheet in position on the working surface of the support member.

9. .A bookkeeping device comprising a writing board on which a first record sheet may be placed, a peg rail extending along the upper surface of said board near one side edge thereof, said rail being adapted to receive an edge of said record sheet beneath the rail and vertically between the rail and board to retain the sheet on the board, said one side of the board being turned upwardly and then being doubled back above said rail and above and generally parallel to said upper surface of the board to form a guide channel slidably receiving said rail and guiding it for longitudinal sliding movement while said edge of the record sheet is confined vertically between said rail and board, said rail having a plurality of pegs projecting upwardly therefrom and adapted to be received in corresponding apertures in the edge of a second record sheet overlying said first sheet to locate said second sheet relative to the rail and thereby move the second sheet with the rail upon said shifting movement thereof, said pegs being positioned laterally beyond and projecting upwardly higher than said doubled back edge of the board, said rail having an undersurface for engaging said first sheet and slidable along the upper surface thereof upon said longitudinal shifting movement of the rail, and projections extending upwardly from said board and engageable with said first sheet in a relation retaining the latter against movement with said rail when the latter is shifted longitudinally.

10. A bookkeeping device comprising a writing board on which a first record sheet may be placed, a rail extending along the upper surface .of said board near one side edge thereof, said ra-il being adapted to receive an edge of said record sheet beneath the rail and vertically between the rail and board to retain the sheet on the board, said rail having locating means for engaging an edge of a second record sheet which overlies the first sheet and operable to hold said second sheet in a predetermined position relative to the rail, means carried by the board guiding the rail for longitudinal shifting movement relative to the board and relative to said second sheet while said edge thereof is confined vertically between said rail and board to thereby shift said second sheet relative to said first sheet, said rail having an under surface for engaging said first sheet and slidable along the upper surface thereof upon said longitudinal shifting movement of the rail, and means carried by said board for engaging said first sheet and holding it against movement with said rail when the latter is shifted longitudinally, said last mentioned means comprising projections extending upwardly from said board and engageable with said first sheet to retain it against movement with the rail when the latter is shifted longitudinally.

11. A bookkeeping device comprising a writing board on which a first record sheet may be placed, a rail extending along the upper surface of said board near one side edge thereof, said rail being adapted to receive an edge of said record sheet beneath the rail and vertically between the rail and board to retain the sheet on the board, said rail having pegs at its upper side receivable within apertures formed in an edge of -a second record sheet which overlies the first sheet and operable to hold said second sheet in a predetermined position relative to the rail, and means carried by the board guiding the rail for longitudinal shifting movement relative to the board and relative to said second sheet while said edge thereof is confined vertically between said rail and board to thereby shift said second sheet relative to said first sheet, said rail having an under surface for engaging said first sheet and slidable along the upper surface thereof upon said longitudinal shifting movement of the rail, said last mentioned means comprising projections extending upwardly from said board and engageable with said first sheet to retain it against movement with the rail when the latter is shifted longitudinally.

12. A bookkeeping device comprising a writing board on which a first record sheet may be placed, a rail extending along the upper surface of said board near one side edge thereof, said rail being adapted to receive an edge of said record sheet beneath the rail and vertically between the rail and board to retain the sheet on the board, said rail having pegs at its upper side receivable within apertures formed in an edge of a second record sheet which overlies the first sheet and operable to hold said second sheet in a predetermined position relative to the rail, and means carried by the board guiding the rail for longitudinal shifting movement relative to the board and relative to said second sheet while said edge thereof is confined vertically between said rail and board to thereby shift said second sheet relative to said first sheet, said rail having an under surface for engaging said first sheet and slidable along the upper surface thereof upon said longitudinal shifting movement of the rail, said last mentioned means comprising projections extending upwardly from said board and engageable with said first sheet to retain it against movement with the rail when the latter is shifted longitudinally, said projections being so located as to retain the rail against lateral movement to thereby assist in guiding the rail for said longitudinal movement.

13. In an accounting board device, the combination of: a support member having a working surface adapted to support a base sheet thereon, a lip extending along one edge of the support member overlying a portion of said surface, a series of abutment elements formed integrally with the support member and projecting above the working surface, a peg rail provided with a plurality of upstanding pegs spaced longitudinally thereof, said lip overlying a portion of said peg rail, said lip and abutments cooperating to guide the peg rail so that it may move longitudinally on the upper surface of the base sheet and relative to the support member, whereby the peg rail may clamp the base sheet in position on the working surface.

14. In an accounting board device for supporting an apertured sheet for movement relative to a lower sheet, the combination of: a support member having a working surface and having a lip extending along one edge thereof, the support member being adapted to support the lower sheet on said working surface and with a marginal portion of the sheet extending under the lip, a series of abutment elements formed integrally with the support member and projecting above the working surface, a peg rail provided with a plurality of upstanding pegs spaced longitudinally thereof and adapted to project through apertures in the upper sheet, said lip and abutments cooperating to guide the peg rail so that it may move longitudinally relative to the support member, said lip overlying a portion of the peg rail, whereby the peg rail may cooperate with the lip and abutments to clamp the lower sheet in position on the working surface of the support member.

15. In an accounting board device, the combination of: a support member having a substantially flat working surface and provided with lip means thereon, the working surface being adapted to support a base sheet thereon, a series of abutment elements formed integrally with the support member and projecting above the working surface and adapted to form indentations in the base sheet, a peg rail having parallel edges and provided with a plurality of upstanding pegs spaced longitudinally thereof, said lip means and abutments cooperating to guide the edges of the peg rail so that it may move longitudinally on the upper surface of the base sheet relative to the support member, whereby the peg rail may clamp the base sheet in position on the working surface.

16. In an accounting board device, the combination of: a metal sheet comprising a support member having a substantially flat working surface and provided with lip means thereon formed integrally from the sheet, a series of abutments formed integrally with the sheet and 9 projecting above the working surface, a peg rail compris- References Cited in the file of this patent ing a flat metal strip having parallel edges and Provided UNITED STATES PATENTS With a plurality of upstanding pegs spaced longitudinally thereof, the peg rail being mounted between the lip 2,520,854 P001 29,1950 means and the series of abutments, the lip means over- 5 2,718,413 FIaHHSOH et a1 Sept. 20, 1955 lying one edge of the metal strip, and the top of the FOREIGN PATENTS abutments being substantially flush with the upper surface of the metal strip, said lip means and abutments cooperating to guide the edges of the strip so that the peg rail may move longitudinally relative to the support 10 member. 

1. A BOOKKEEPING DEVICE COMPRISING A WRITING BOARD ON WHICH A FIRST RECORD SHEET MAY BE PLACED, A PEG RAIL EXTENDING ALONG THE UPPER SURFACE OF SAID BOARD NEAR ONE SIDE EDGE THEREOF, SAID RAIL BEING ADAPTED TO RECEIVE AN EDGE OF SAID RECORD SHEET BENEATH THE RAIL AND VERTICALLY BETWEEN THE RAIL AND BOARD TO RETAIN THE SHEET ON THE BOARD, SAID ONE SIDE OF THE BOARD BEING TURNED UPWARDLY AND THEN BEING DOUBLED BACK ABOVE SAID RAIL AND ABOVE AND GENERALLY PARALLEL TO SAID UPPER SURFACE OF THE BOARD TO FORM A GUIDE CHANNEL SLIDABLY RECEIVING SAID RAIL AND GUIDING IT FOR LONGITUDINAL SLIDING MOVEMENT WHILE SAID EDGE OF THE SECOND SHEET IS CONFINED VERTICALLY BETWEEN SAID RAIL AND BOARD, SAID RAIL HAVING A PLURALITY OF PEGS PROJECTING UPWARDLY THEREFROM AND ADAPTED TO BE RECEIVED IN CORRESPONDING APERTURES IN THE EDGE OF A SECOND RECORD SHEET OVERLYING SAID FIRST SHEET TO LOCATE SAID SECOND SHEET RELATIVE TO THE RAIL AND THEREBY MOVE THE SECOND SHEET WITH THE RAIL UPON SAID SHIFTING MOVEMENT THEREOF, SAID PEGS BEING POSITIONED LATERALLY BEYOND AND PROJECTING UPWARDLY HIGHER THAN SAID DOUBLED BACK EDGE OF THE BOARD, SAID RAIL HAVING AN UNDERSURFACE FOR ENGAGING SAID FIRST SHEET AND SLIDABLE ALONG THE UPPER SURFACE THEREOF UPON SAID LONGITUDINAL SHIFTING MOVEMENT OF THE RAIL, AND MEANS PROJECTING UPWARDLY FROM SAID BOARD AT A LOCATION TO ENGAGE THE UNDERSIDE OF SAID FIRST SHEET AND HOLD IT AGAINST MOVEMENT WITH SAID RAIL WHEN THE LATTER IS SHIFTED LONGITUDINALLY. 